Earliest Sea Scorpion from China
The ancient animal lived during the uppermost Ordovician period, around 445 million years ago.
It had a parabolic head shield (carapace), simple appendages with paired spines, swimming paddles and a streamlined body.
Eurypterids, horseshoe crabs, scorpions and the other arachnids are united in a group of primitive arthropods called chelicerates that have claw-like front appendages.
An eurypterid is essentially the head of a horseshoe crab, some with big claws and swimming paddles, on the body of a scorpion, but with gills and no poison sting. It likely fed on small prey such as mollusks, crustaceans and worms.
The fossil was found in the Wenchang Formation of Anji County, Zhejiang Province, South China.
Unusually, it occurs alongside diverse sponges and other invertebrates that indicate a deep (several hundred meters) marine environment, although it probably washed in from a more typical shallow marine environment.
It is also the earliest known example of an adelophthalmid eurypterid — the longest-lived group, and indicates that eurypterids may have diversified in Gondwana, an ancient supercontinent of the southern hemisphere.
“This fossil is important because it’s the oldest sea scorpion found in China and it improves our knowledge of the early evolutionary history of extremely rare early eurypterids,” said Dr. Han Wang, from the Nanjing Institute of Geology and Palaeontology, lead author of the study.
Source: Sci News